ELN 2017 Genetic Risk Stratification Predicts Survival of Acute Myeloid Leukemia Patients Receiving Allogeneic Hematopoietic Stem Cell Transplantation

Abstract

European LeukemiaNet (ELN) 2017 risk stratificationbygenetics is prognostic of outcomes in patients with acute myeloid leukemia (AML). However, the prognostic impact of the 2017 ELN genetic risk stratification after allogeneic hematopoietic cell transplantation (alloHCT) is not well established. We examined the effect of 2017 ELN genetic risk stratification on alloHCT outcomes of AML. We included 500 adult (≥18 years) AML patients in first (n=370) or second (n=130) complete remission receiving alloHCT from 2005 to 2016. Patients were classified into favorable (12%), intermediate (57%), and adverse (32%) 2017 ELN risk groups. The Cox proportional hazard model was used to conduct the multivariable analyses of leukemia-free survival (LFS) and overall survival (OS). Relapse and nonrelapse mortality were analyzed by the Fine-Gray regression model. OS at 2 years was 72% in the favorable versus 60% in the intermediate versus 45% in the adverse risk groups (P < .001). In multivariable analyses, the 2017 ELN classifier was an independent predictor of OS after alloHCT with significantly higher overall mortality in the intermediate (hazard ratio [HR]=1.68, 95% confidence interval [CI], 1.06-2.68; P=.03) and adverse (HR=2.50, 95% CI, 1.54-4.06; P < .001) risk groups compared to the favorable risk group. Similarly, LFS was worse in the intermediate (HR=1.63, 95%, CI 1.06-2.53; P=.03) and adverse (HR 2.23, 95% CI, 1.41-3.54; P < .001) risk groups while relapse was higher in the adverse risk group (HR=2.36, 95% CI, 1.28-4.35; P=.006) as compared to the favorable risk group. These data highlight the prognostic impact of the 2017 ELN genetic risk stratification on the survival of AML patients after alloHCT. Patients in the adverse risk group had the highest risk of relapse and worst survival. Thus the 2017 ELN prognostic system can help identify AML patients who may benefit from clinical trials offering relapse mitigation strategies to improve transplant outcomes.